Charles Ellicott Commentary Leviticus 4:32

"And if he bring a lamb as his oblation for a sin-offering, he shall bring it a female without blemish." — Leviticus 4:32 (ASV)

And if he bring a lamb. — Better, a sheep. (See Leviticus 3:7.) Those who were unable to bring a goat might offer a female sheep as the less valuable animal, provided it was without blemish. Though the ritual is the same as with the goat , yet the sheep is treated separately, because of the fat tail, which had to be burned. (See Leviticus 3:12.)